Systematic prospective observational studies, of which this project is an excellent example, have led to significant progress in the applications of orthognathic surgery to treatment of dentofacial deformity. Options now exist for patients who might not have been recommended for treatment previously, and the appropriate treatment methods have been clarified. [unreadable] [unreadable] In the continuation of this project, we plan to evaluate remodeling of the mandibular condyles as a factor in post surgical stability that has not been adequately evaluated previously. A new cone-beam CT instrument specialized for maxillofacial imaging now makes it feasible to follow these changes and relate them to treatment outcomes. This may be of particular interest in patients with facial asymmetry. Further information about stability and influences on it is needed to assess more completely the orthognathic surgery procedures that have been assessed so far only in a preliminary way (for example, maxillary / two-jaw surgery for Class III problems, correction of facial asymmetry) and to update the existing data base to document the effect of changes in technique (such as the replacement of metal with resorbable devices for rigid internal fixation). To document the benefits of treatment for dentofacial problems, it is important to evaluate not only the morphologic and functional changes but also what patients perceive and experience, both short- and long term. We will evaluate influences on patient satisfaction and health-related quality of life, with emphasis on how perceptions of a surgical experience are affected by anxiety and psychologic distress. Data for this relationship in the systemically healthy population who are candidates for orthognathic surgery will be more widely generalizable than data from chronically ill subjects, and can lead to improved patient preparation for surgery and patient management after surgery. [unreadable] [unreadable]